Vapor degreaser

ABSTRACT

A portable degreaser comprising two concentric tanks separated by a perforated wall. The concentric tanks are an immersion tank located within a solvent-boiling tank which serves as an offsetvapor-generating sump. The rinse and spray area above the immersion tank is surrounded by a perforated wall. Boiling solvent is on the other side of the wall. Condensing coils encircle the perforated wall at the top of the spray area and thus, are exposed to the vapor an all sides. A gutter immediately below the condensing coils returns the condensed liquid into a separate distillate tank equipped with a water separator. The spray jets are supplied with the distilled solvent from the distillate tank. The distillate is kept hot since the lower portion of the tank is positioned within the boiling sump.

United States Patent Primary Examiner-Daniel Blum AttorneyAlter, Weiss &Whitesel ABSTRACT: A portable degreaser comprising two concentric tanksseparated by a perforated wall. The concentric tanks are an immersiontank located within a solvent-boiling tank which serves as anoffset-vapor-generating sump. The rinse and spray area above theimmersion tank is surrounded by a perforated wall. Boiling solvent is onthe other side of the wall. Condensing coils encircle the perforatedwall at the top of the spray area and thus, are exposed to the vapor anall sides. A gutter immediately below the condensing coils returns thecondensed liquid into a separate distillate tank equipped with a waterseparator. The spray jets are supplied with the distilled solvent fromthe distillate tank. The distillate is kept hot since the lower portionof the tank is positioned within the boiling sump.

PATENIED JUL2 0 ran SHEET 1 BF 3 FIG! INVENTOR DAVID GOLDWARE ATTORNEYSPATENTEU JUL20 ISYI SHEET 2 OF 3 INVENTOR DAVID GGLDWARE ATTORNEYS VAPORDEGREASER The invention relates to vapor degreasers, and more particularly, to degreasers that provide a combination dip, spray and vaporcleaning facility as well as solvent vapor dryers.

A problem with present day vapor degreasers is the loss of solvent whichescapes past the condenser coils due to penetration of the interfacebetween boiling and refrigeration temperatures. This occurs due tovapor-air diffusion caused by the boiling action of the solvent within acompletely open top tank. The perforated wall separating the twoconcentric tanks virtually eliminates this vapor-air diffusion. Also,the interfacing capacity of refrigerate coils on the presently availabledegreasers are limited because the coils are located on the ex teriorwalls of the degreaser tank and thus, present only a limited surface tothe vapor as it passes the coils.

Also encountered by present day vapor degreasers is restricted workingvolume in the degreaser for handling products to be degreased. Theinefficiency in the use of the cleaning area of the presently availablevapor degreasers is caused by the method of separation of the immersiontank and the boiling tank. A baffle is used to divide one tank. Thebaffle, of course, limits the length of the product being degreased aswell as the width.

A further problem encountered by vapor degreasers is the spraying ofcold distilled solvent. The temperature of the condensing coils isthermostatically controlled. Should cold solvent be sprayed upon thecondensing coils when it is about to call for refrigeration, anunbalanced temperate condition is set up. Hot vapors surrounding thesecoils demand refrigeration at the right time otherwise the vapors escapepast the coils and are lost. This is costly as well as uncomfortable dueto the escaping fumes. A further disadvantage is that cold solvent isnot as efficient a cleaning agent as hot.

Accordingly, an object of this invention is to provide a unique vapordegreaser.

A related object of the tank is to provide vapor degreasers wherein therefrigerate coils are not mounted on any closed walls.

Yet, another object of this invention is to provide vapor degreaserswherein no baffle is required between the immersion tank and the boilingtank. Thus, no baffle is located within the rinse and spray workingarea.

Yet, another object of this invention is to provide a vapor degreaserhaving a heated reserve distillate tank equipped with a water separatorthat is connected directly to gutters located below the refrigeratecoils so that only clean, freshly distilled solvent is pumped throughthe sprays.

Another object of this invention is to create a double boiler effectwherein the boiling action is restricted to the outer con centric tankonly, by means of-slightly elevating the inner concentric tank.

Briefly, an exemplary embodiment of this invention accomplishes theseand other objects by means of an immersion tank that is located within aboiling tank. The boiling tank serves as an offset-vapor-generatingsump. Since the vapor-producing tank is located outside the immersiontank within the complete degreasing unit, vapor pressure tends to risearound the immersion tank as well as the spray area and is reduced by 60percent before flowing through the perforated wall towards the openingat the top of the degreaser through which the product to be degreased isput into the degreasing spray and rinse area. The spray and rinse areais surrounded by this perforated wall. The perforated wall is surroundedby the refrigerate coils at some point near the top thereof. Thus, whilethe refrigerate coils are exposed to vaporized solvent on all sides thevapors within the rinse and spray area are relatively static and performmuch more efficiently. Vapor-air diffusion is minimized. A gutterlocated beneath the refrigerate coils catches the distilled, condensedsolvent and returns it to a reserve distillate tank that is equippedwith a water separator. Sprays are supplied from the reserve distillatetank.

The abovementioned and other features and objects of this invention andthe manner of attaining them will become more apparent and the inventionitself will be best understood, by reference to the followingdescription of an embodiment of an invention taken in conjunction withthe accompanying drawings, wherein:

FIG. 1 pictorially shows the complete inventive vapor degreasing unit;

FIG. 2 is an exploded view of that portion of the tank into which thework product being degreased may enter;

FIG. 3 is a semisectional front view of the complete degreaser showingthe assembly of the central units of the degreaser;

FIG. 4 is a top sectional view of the degreaser unit looking in thedirection of the arrows 4-4 of FIG. 3; and

FIG. 5 is a sectional view of the distillate reserve tank look ing inthe direction ofthe arrows 5-5 in FIG. 3.

Similar characters of reference indicate corresponding parts andfeatures throughout the several views, and referring now to the same;the character 10 indicates the complete vapor degreasing unit. Thedegreaser unit as best shown in FIG. 1, comprises a unit which may bemounted on casters, such as caster l], for portability. The completeunit is made up of two r sections, the degreasing section llll and thecontrol and refrigerating section 12. The control and refrigeratingunits are located beneath panel 114. The degreasing section lllcomprises a cover 15 closing the opening of the freeboard above thespray and rinse area. The cover has in the middle thereof a handle 17enabling its easy removal from the opening.

The degreasing area of the vapor degreaser unit as best shown in FIG. 2,comprises a freeboard section 118, a rinse and spray area wall separator19 comprised of perforated material and an immersion tank 21. The rinseand spray area wall 19 is encircle near the top thereof by condenser orrefrigerate coils 22. Apertures, such as apertures 23, are provided inthe perforated wall 19 to enable spray from the jets 25 to passtherethrough. The tubing 24 leads to spray jets, such as spray jet 25shown in FIGS. 3 and 4.

The control panel 13 comprises switches and indicators for controllingthe degreaser unit. Thus, there is shown a boiling tank liquid levelindicator 26 and a reserve distillate tank liquid level indicator 27.The switches include: switch 28 for controlling an idling heater strip,switch 29 which controls a main heater strip, and switch 31 whichcontrols the refrigerator unit. A spray control switch, such as switch32, is shown. A spray cycle timer, if one is desired, is controlled byswitch 33. Red warning light 34 is in conjunction with a low solventlevel safety mechanism which automatically shuts off all heaters.

A drain cock is provided as illustrated at 36 for removing all of thesolvent from the unit. Alternatively, a drain cock 36a is provided forpurifying and reclaiming dirty solvent through distillation.

As is apparent in FIGS. 2 and 3, the freeboard section 18 rests on topof the outer cabinet 16 on its flange 38. A peripheral offset 39 islocated at the bottom of the freeboard section. The peripheral offset 39fits over the top of the perforated wall section 19. The wall section 19fits within the peripheral offset section 41 of the immersion tank 21. Adrain 42 covered by stainless steel mesh filter is located near thebottom of the immersion tank 21, to facilitate draining the tank, duringcleaning operations, for example.

The operation and the assembly of the combined units is best seen inFIG. 3. A vapor-generating boiling tank, 43 extends upward to the middleportion of freeboard l3 and surrounds most of the assembly of the unitsshown in FIG. 2.

Means are provided for capturing the condensed fluid. More particularly,gutter 44 extends beneath the condensing coils 22 and is coupled into aseparate distillate reserve tank 46 through piping 47. The distillatereserve tank 46 is positioned so that it is partly submerged within theboiling sumps, as indicated by boiling level line A-A.

The distillate reserve tank 46 is shown in greater detail in FIG. 5. Itserves to hold the freshly distilled solvent for use in sprayingarticles being degreased. The tank is equipped with a float 48. Thefloat in moving varies an impedance; for example, which changes a signalthereacross. The impedance leads to conductors 49, which are connectedto reserve distillate tank liquid level indicator 27.

Means are provided within the tank 46 to separate any water from thecondensed solvent. More particularly, tank 46 includes a baffle 51 whichpartitions the water separator por tion of tank 46 from the rest of thetank. The water separator portion 52 is directly under the input pipe 47through which the condensed solvent flows from gutter 44. Thus, thecondensed solvent enters the tank 46 through the water separator portion52. The solvent is heavier than water so that the water floatsthereupon. An outlet 53 is located near the top of the water separatorportion 52 of the reserve tank 46 so that when portion 52 fills up withwater and solvent sufficiently high to enable the water to flow out ofoutlet 53, the water is removed from the unit. The water flows throughoutlet 53 to a shallow evaporator pan (not shown) which is placed in thevicinity of the refrigerator fan unit. Thus, the evaporation of thewater is accomplished and the necessity of connecting to externalplumbing to carry the water away is obviated. It should be noted thatbaffle 51 cooperates with smaller baffle 51a to maintain the water inthe water separator unit.

Means are provided to enable solvent from tank 46 to flow into tank 43.In greater detail, an overflow outlet 54 is located in the reservesolvent portion of the tank to enable the solvent, when it reaches thislevel in the tank, to flow directly into the boiling tank 43.

Means are provided for transmitting the freshly distilled solvent to thejet sprays. ln greater detail, at the bottom of the reserve tank is anoutlet and piping 56 which leads to pump 57. The pump 57 is thenconnected to the jet sprays, such as spray through pipe 24. Thus, thesprays are supplied with freshly distilled solvent at all times in theoperating cycle of this degreaser.

The sprayed fluid which is emitted from jet sprays, such as jet spray25, falls into the immersion tank 21. The liquid solvent in theimmersion tank is indicated by numeral 58. Thus, flow occurs fromboiling tank 43 where the solvent is vaporized, to condenser coils 22where the solvent is condensed, gutter 44, tank 46, pump 57, spray jets,such as spray jet 25 to immersion tank 21.

When the immersion tank overflows, the solvent falls back into tank 43and at the same time is filtered through a fine stainless steel mesh atthe overflow height in order to prevent any floating particulate matterfrom entering the outer concentric tank.

Means are provided for preventing solvent 58 in immersion tank 21 fromboiling. in greater detail, tank 21 has legs, such as leg 59, whichmaintain space 60 between the bottom 61 of boiling tank 43 and thebottom 62 of immersion tank 21. The space acts to insulate the immersiontank from the heat of the heating elements; such as element 63 locatedin the heating compartment 64. The heat generated by the heating elementin compartment 64 is sufficient to boil the fluid solvent in tank 43,but is prevented from boiling the solvent in tank 21 by the fact thattank 21 is not directly contiguous to the bottom 61 of the tank 43.

Means are provided in boiling tank 43 for properly locating theimmersion tank 21. More particularly, angle irons 64, 66 located onfloor 61 of tank 43 abut the legs, such as leg 59, of

tank 21 to properly locate that tank when it is lowered into position intank 43.

Means are provided for monitoring the height of the boiling solvent,designated as 67, in the boiling tank 43. More particularly, a float 68is coupled to variable impedance means 69 which is connected toindicator 26 on the control panel. This provides a feature whereby theheight of the boiling solvent is continuously monitored. The impedancemeans 69 is shown in FIG. 4; switching means could, of course, be usedin place of the impedance means. The essential matter is that a safetymechanism is provided for monitoring the level of the boiled liquid.Additional safety features include a thermostat 71 which automaticallyturns off the heating unit when the boiling solvent 68 becomes too hot.

The outer tank or boiling tank 43 has a bottom floor section 72 whichdefines the bottom of the heating space 64. Spacers, such as spacer 73,are used to space the boiling tank 43 from the bottom floor 74 ofthecabinet 16.

Means are provided for completely draining the solvent from thedegreaser unit. More particularly, a valve 76 attaches to outlet 42 onthe inner tank or immersion tank 21. The valve is controlled by valvecontrol handle 77 which extends through the top section 78 of tank 43. Along stem 79 reaches from handle 77 to valve 76. The immersion tanksolvent 58 is emptied into boiling tank 43 through a fine stainlesssteel mesh filter when it is desired to drain all the fluid from thedegreaser unit. Bottom floor 61 of tank 43 has an outlet 81 which leadsto drainage pipe 82 and through valve 36 to outlet drain 83. Openingboth valves enables the removal of all solvents from the degreaser unit.

As an alternative to drainage through outlet 81, most solvent may beremoved by distillation and pumped out of distillate reserve tank as itis purified.

The refrigerating unit 84 is shown in FIG. 3. Tubing 22a and 22b leadfrom the refrigerating unit to refrigerate coils 22 in tank 43. Therefrigerating unit may rest on spacers such as spacer 86.

Means are provided for maximizing the operating efficiency of coils 22.That is, the condensing coils 22 are not mounted on a closed wall,rather they are mounted on perforated wall 19 and thus, are exposed tothe vapor on all sides.

Means are provided for maximizing the working space available in therinse and spray area and in the boiling tank. This is accomplished inthat the immersion tank is set within the boiling tank. Theconfiguration of the boiling tank 43 surrounding immersion tank 21 doesaway with baffling in the rinse and spray area. This makes it possibleto degrease larger products than would be possible with the normallyoperated degreasing machines that have baffling between immersion andboiling sections within the tank.

The controls used in this degreasing machine are those which arenormally found on similar type degreasing units. Thus, for example, al0-second spray is available by actuation of the proper switch, such asswitch 32, for example. The switch activates a time delay cycleapparatus whereby the machine is automated to give a lO-second spraycycle. This may be changed to a S-second spray cycle, if so desired, orany other useful time delay required.

A foot switch may be provided to operate the spray jets if so desired.Electrical circuitry for these controls is not shown herein because itis believed that it is obvious to those skilled in the art.

A thermostat control 88 is located above condensing coils 22. Thisthermostat control operates to turn the machine off if the vapor levelshould rise too high or the refrigeration unit should break down and thecondensing coils are not operating. Then vapor would reach thermostatcontrol 88 causing it to heat and turn off the degreasing machineheaters.

All of the degreaser parts are preferably made from stainless steelsheet metal. One of the heating strips is so wired in heating section 64whereby the degreasing machine can be idled overnight under low wattagewithout having to turn the machine off. The overnight idle enables thereserve tank to refill, and precludes the necessity of having a warmuptime before using the machine.

Of further importance is the fact that while the machine is on idleheat, the vapor zone is maintained. Loss of the vapor zone is a loss ofexpensive solvent. Idling the machine obviates the necessity toreestablish the vapor zone.

While not shown, an electric cable connects the degreasing machine to apower source. Also not shown are the electrical controls and theconnections between the floats and thermostats and the control panel.These details are well known to those skilled in the art.

In operation, the vapor degreaser is turned on. The refrigeration unitsends refrigerant through the condensing coils 22 mounted on meshperforated wall 19. The heating units, such as heating units 63 causesthe solvent in tank 43 to boil. The vapor fills the area outside theperforated wall as well as the rinse and spray area surrounded byperforated wall 19 but is prevented from going higher than the coils 22by the efiicient condensing action of coils 22. Since the coils 22 areexposed to vapor on all sides it condenses a much greater capacity ofvapor than the available units that mount their coils on an exteriorwall and thus remove a large portion of the operating area of the coils.

The condensed solvent is fed into reserve tank 46. From there it ispumped through jet sprays mounted in the spray and rinse area. Thesprayed solvent returns to the immersion tank 21.

The cover is removed to place articles for degreasing into the machine.The high freeboard, and especially the offset vapor generator as well asthe efficient action of the condensing coils prevents any vapor fromescaping through the opening at the top of the cabinet H6. The articleis held in the vapor below coils 22 or immersed in the tank 41 and thensprayed. Thus, the article for degreasing is subjected to the degreasingeiTects of immersion, vapor and spray. The absence of any baffle in therinse and spray area or in the immersion tank makes it possible toservice larger size articles than could be done in similar-sizeddegreasing units. In addition, there is no necessity of moving thearticle, other than lowering and raising it to go from an immersion stepto a vapor-processing step and vice versa.

While I have described the above principles of my invention, inconnection with specific apparatus, it is to be clearly understood thatthis description is made only by way of example and not as a limitationon the scope of my invention,

lclaim:

1. A degreaser unit for degreasing articles of manufacture,

said unit comprising an outer cabinet,

said cabinet having therein a vapor-generating tank for convertingliquid solvent into vapor,

heating means associated with said vapor-generating tank to provide theheat to cause said solvent to boil and provide vapor,

means for condensing said vapor to prevent the vapor from leaving saiddegreaser unit,

immersion tank means located within said vapor-generating tank,

said immersion tank means being surrounded on all sides by the solventin said vapor-generating tank, and

legs on said immersion tank to keep the bottom of said immersion tankseparated from said heating means to thereby keep the solvent withinsaid] immersion tank from boiling.

2. The degreaser unit of claim ll, wherein a rinse and spray area isprovided above said immersion tank, and

wherein said rinse and spray area is surrounded by perforated wallmeans.

3. A degreaser unit for degreasing articles of manufacture, said unitscomprising an outer cabinet,

said cabinet having therein a vapor-generating tank for convertingliquid solvent to vapor,

heating means associated with said vapor-generating tank to provide theheat to cause the solvent to provide vapor, means for condensing saidvapor to prevent the vapor from leaving said degreaser unit,

immersion tank means located within said vapor-generating tank, legs onsaid immersion tank to keep the bottom of said immersion tank separatedfrom said heating means to thereby prevent the solvent within saidimmersion tank from boiling,

a rinse and spray area located above said immersion tank,

said rinse and spray area being surrounded by perforated wall means, and

said means for condensing said vapors comprising refrigerate coilsattached to said perforated wall means, thereby maximizing exposure ofsaid coil means to the vapor.

4. The degreaser unit of claim 3 wherein gutter means are provided belowsaid coil means to trap solvent condensed by said coil means, and

reserve distillate tank means for receiving said condensed solvent,

spray jet means in said spray and rinse area, and

means for passing said condensed solvent from said reserve distillatetank through said spray jet means under pressure to provide a spray ofcondensed solvent.

5. The degreaser unit of claim 4 wherein the distillate tank is sopositioned as to be partly submerged within the liquid solvent in thevapor-generating tank.

6. The degreaser unit of claim 5 wherein said reserve distillate tank isprovided ti ith water separator means to assure a spray of pure solvent.

7. The degreaser unit of claim 6, wherein level indicator means areprovided to indicate the level of solvent in said vapor-generating tank.

8. The degreaser unit of claim 7 wherein said perforated wall means islocated and held between said immersion tank and a freeboard section,and

flange means on said freeboard section whereby said freeboard sectionrests on the top of said cabinet at an article insertion opening.

1. A degreaser unit for degreasing articles of manufacture, said unitcomprising an outer cabinet, said cabinet having therein avapor-generating tank for converting liquid solvent into vapor, heatingmeans associated with said vapor-generating tank to provide the heat tocause said solvent to boil and provide vapor, means for condensing saidvapor to prevent the vapor from leaving said degreaser unit, immersiontank means located within said vapor-generating tank, said immersiontank means being surrounded on all sides by the solvent in saidvapor-generating tank, and legs on said immersion tank to keep thebottom of said immersion tank separated from said heating means tothereby keep the solvent within said immersion tank from boiling.
 2. Thedegreaser unit of claim 1, wherein a rinse and spray area is providedabove said immersion tank, and wherein said rinse and spray area issurrounded by perforated wall means.
 3. A degreaser unit for degreasingarticles of manufacture, said units comprising an outer cabinet, saidcabinet having therein a vapor-generating tank for converting liquidsolvent to vapor, heating means associated with said vapor-generatingtank to provide the heat to cause the solvent to provide vapor, meansfor condensing said vapor to prevent the vapor from leaving saiddegreaser unit, immersion tank means located within saidvapor-generating tank, legs on said immersion tank to keep the bottom ofsaid immersion tank separated from said heating means to thereby preventthe solvent within said immersion tank from boiling, a rinse and sprayarea located above said immersion tank, said rinse and spray area beingsurrounded by perforated wall means, and said means for condensing saidvapors comprising refrigerate coils attached to said perforated wallmeans, thereby maximizing exposure of said coil means to the vapor. 4.The degreaser unit of claim 3 wherein gutter means are provided belowsaid coil means to trap solvent condensed by said coil means, andreserve distillate tank means for receiving said condensed solvent,spray jet means in said spray and rinse area, and means for passing saidcondensed solvent from said reserve distillate tank through said sprayjet means under pressure to provide a spray of condensed solvent.
 5. Thedegreaser unit of claim 4 wherein the distillate tank is so positionedas to be partly submerged within the liquid solvent in thevapor-generating tank.
 6. The degreaser unit of claim 5 wherein saidreserve distillate tank is provided with water separator means to assurea spray of pure solvent.
 7. The degreaser unit of claim 6, wherein levelindicator means are provided to indicate the level of solvent in saidvapor-generating tank.
 8. The degreaser unit of claim 7 wherein saidperforated wall means is located and held between said immersion tankand a freeboard section, and flange means on said freeboard sectionwhereby said freeboard section rests on the top of said cabinet at anarticle insertion opening.